A reader left on comment on Stoicism: Weak Criticisms asking "Do you have any critics for stoicism?". I don't want address any specific weakness of Stoic philosophy but instead concentrate on what I believe their philosophy lacks.
Stoicism, at it's core, is a defensive philosophy whose central goal is developing psychological resilience against an ever changing and often harsh world. It teaches true tranquility lies within the inviolable inner citadel of the human soul, a citadel fortified through sacrificing strong attachments to family and friends and worldly goods. It is the slave learning to accept his chains and declaring himself freer than his master, the prisoner embracing his captivity, the solitary man finding pride in his loneliness.
There is no concept of zest in Stoicism, of freeing yourself from self-imposed shackles to embrace and enjoy all life can offer. Our dreams and our hopes are treated as dangerous vices as they lie beyond our control and must be eradicated through daily philosophical mediation. Nostalgia, that bitter sweet emotion which arises from looking back over our lives and finding continuity and meaning in our very existence, is but to be guarded against for only the present truly exists. Joy is categorized with anger as threat to Stoic tranquility.
In essence, Stoicism leaves everything untouched. Our life and our world are in the hands of the logos; only our emotions are ours to control. This is the philosophical equivalent of an anti-depressant drug which alters our emotions while leaving unchanged the conditions which gave rise to them. But human beings, especially unhappy human beings, need more. We need to struggle to realize our hope that our condition can change however irrational that hope may be. The Stoic introspective struggle for virtue is not enough; we need to shatter the walls which surround us, not learn to accept them.
What Stoicism lacks is all that is life-affirming.